ABSTRACT Two hundred and forty Japanese quail aged 125 days were randomly allocated to five treatment groups based on laying (%) and quail’s weight (90.71 ± 1.8% egg/day × 100 and 178.05 ± 9.38 g, respectively), each of which included six replicates of eight quails. The diets were formulated based on corn, soybean meal, and industrial amino acids. An optimal diet achieves 100% of amino acids required by the quail requirements, except for threonine. Five treatments were made: 20% less amino acid; 10% less amino acid; optimal diet; 10% more amino acid; and 20% more amino acids than those in the optimal diet. The increase in amino acid levels in a fixed Lys: amino acid ratio led to histological alterations in the liver and uterine epithelium, reduction in blood lipid peroxidation, lower hepatic HSP70 gene expression, and the performance of laying Japanese quail. The optimal diet based on the NRC with an adjusted Thr: Lys 78 ratio (Lys 1.0%) improved the performance and efficiency of Japanese quail from 125 to 230 days of age.

ABSTRACT Emulsifiers and exogenous lipases are feed additives used to increase lipid utilization in broiler diets. A meta-analysis was carried out to quantify the effects of the supplementation of emulsifiers and exogenous lipases on broiler weight gain (BWG, g/broiler/d) and feed conversion ratio (FCR, g/g) during the whole production cycle. Studies were obtained from the PubMed, Scielo, Science Direct, Scopus, and Web of Science databases. A total of 2669 studies were identified, 25 of which composed the database for the meta-analysis, representing data from a total of 14,643 broilers. These results demonstrate that there is evidence in the literature supporting that supplementation with emulsifiers or lipases improves broiler weight gain and feed conversion during the whole production cycle. However, the effect of the additives is influenced by bird sex, lipid source and concentration, type of additive and concentration, energy level of the feed, and bird strains. The isolated use of emulsifiers increases weight gain by 1.62g/day and reduces feed conversion by 0.04. However, there is no evidence that exogenous lipase use alone improves weight gain or feed conversion in broilers during the whole production cycle. The latter result may be due to the small number of studies with the additive in question, rather than its possible effects on weight gain and feed conversion. Therefore, further investigation should be conducted on this topic, especially studies on females fed diets supplemented with lipases.

ABSTRACTThe objective of this study was to evaluate the effects of 1% dietary glutamic acid on the body weight, intestinal morphometry, and anti-Newcastle antibody titers of broiler chickens submitted to heat stress. One-d-old male broiler chicks (n=120) were distributed according to a 2 x 2 factorial design with two environmental temperatures (thermoneutral or heat stress) and two diets (with 0 or 1% glutamic acid). Heat stress temperature was constantly maintained (24h/day) 5 ºC higher than the thermoneutral temperature. Diets supplied the nutritional requirements of broilers in the pre-starter (1 to 7d) and starter (8 to 21d) phases. Birds were vaccinated against Newcastle disease on d 7 via eye drop. On days 5, 10, 15, and 20, individual body weight was determined, serum samples were collected from five birds, and duodenum samples were collected from four birds per treatment. Serum anti-Newcastle antibody titers were determined by enzyme immunoassay and transformed into log10. Villus height, crypt depth, and villus: crypt ratio were measured in the duodenum. Data were analyzed by ANOVA. Chronic heat stress negatively affected body weight and intestinal morphometry during the pre-starter and starter phases, but had no effect on antibody titers. Dietary glutamic acid supplementation (1%) improved body weight and intestinal integrity of birds submitted to heat stress when compared with non-supplemented and heat-stressed birds.

High environmental temperatures have a negative effect on the production efficiency of poultry reared in hot climates. This study evaluated the efficiency of electrolyte supplementation under high environmental temperature conditions by manipulating water and feed electrolyte balance (EB) on the survival and performance of European quails. In experiment 1, a completely randomized experimental design was applied in a 4 x 2 factorial arrangement. Treatments consisted in four feed EB values (0, 120, 240, 360 mEq/kg), and two environmental temperatures (25 and 34 ºC). Feed electrolyte balance was manipulated by the addition of sodium bicarbonate and ammonium chloride. In experiment 2, birds were randomly distributed according to a 5 x 2 factorial arrangement. Treatments consisted in five BE values in the drinking water (0, 30, 60, 90, 120 mEq/L) and two environmental temperatures (25 and 34 °C). Only sodium bicarbonate was added to the water to obtain the different BE values. The experiments were carried out simultaneously in environmental chambers at constant temperatures with 20- to 37-d-old quails. Most evaluated parameters were influenced by temperature in both experiments. In experiment 1, EB affected water intake and intestinal length. In experiment 2, EB values influenced (p < 0.05) water intake and heart and liver relative weights. Electrolyte balance values of 120 mEq/kg of feed and of 30 mEq/L of drinking water are recommended to increase water intake of grower European quails reared under hot temperature.

The incorporation of polyunsaturated fatty acids in chicken eggs by adding oils to the diets has been extensively studied. This experiment aimed at evaluating possible changes in the fatty acid profile of the eggs of layers fed diets supplemented with linseed and soybean oils. The experiment was performed using 192 29 week-old laying hens, distributed in a completely randomized design, into six treatments with four replicates of eight birds each. Treatments consisted of a control diet (no vegetable oil) and diets including 2% of vegetable oil. Linseed oil replaced 0, 25, 50, 75, and 100% soybean oil in the diets, corresponding to 0.0, 0.5, 1.0, 1.5, and 2.0% of linseed oil in the diet. A pool of two egg yolks from each treatment was submitted to lipid extraction and fatty acid methylation, and subsequent gas chromatography (GC) analysis to detect seven fatty acids. Saturated (myristic and palmitic) fatty acids concentration was affected by lipid dietary source, with the lowest concentration in birds were fed feeds containing linseed oil. Polyunsaturated fatty acids (PUFA) concentration in the eggs was influenced by different levels of linseed oil inclusion. Linoleic acid egg content increased when linseed oil was used on diet as compared to the control diet. Linseed oil was considered an excellent source of linolenic acid incorporation in the eggs.